A network service provider offers services to subscribers that access a service provider core network using an access network. Services offered may include, for example, traditional Internet access, Voice-over-Internet Protocol (VoIP), video and multimedia services, and security services. The service provider network may support multiple types of access network infrastructures that connect to service provider network access gateways to provide access to the offered services. Services may also be offered by a third-party content provider, e.g., to which the service provider offers connectivity.
Heterogeneous access networks connect many thousands of subscribers to any number of access gateway types, such as Broadband Remote Access Servers (BRASs), Cable Modem Termination Systems (CMTSs), and Gateway GPRS Support Nodes (GGSNs), that may have varying capabilities and scalability limitations and yet face ever-increasing demands for both subscriber connection management and subscriber-specific traffic management services. Although an access gateway, as a connection terminus and thus a transport node for all subscriber traffic for a particular subscriber device, is an established location at which to perform subscriber-specific traffic management services, coupling subscriber access and traffic management at an access gateway may restrict or prevent independent scaling and independent optimization of these disparate functions.
As a result, a service provider may deploy one or more service nodes in the service provider (SP) core network, upstream from the access gateways, to route traffic through the network to servers that provide the subscriber services and to apply carrier edge services such as firewall, carrier grade network address translation (CG-NAT), and load balancing of packet flows for subscribers among one or more servers that provide the subscriber services. In this way, the service nodes are decoupled from the subscriber access management functions and thus may be optimized for service processing.